Good evening,
my engine started knocking after pouring some sealant fix. I just did few test rides, and the sound appared. Oil level is a bit above max, however nothing drastic.

Any Ideas what is the reason behind? I am thinking of changeing the oil with the filter and hope for the best.

I have e150, 2001, V6, 4,2L, with 300k KMs on it.

 

There must have been a reason the additive was added.
Can you enlighten and bring us up to speed on what was going on?
Sometimes people call a valve noise knocking and that is quite different from a lower end engine noise.
Was the engine run without sufficient oil in the engine, which if so , is an entirely different story.